<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>案例二样式</title>
    <style>
        div {
            border: 1px solid red;
            width: 100%;
        }

        .left {
            width: 20%;
            height: 500px;
            float: left;

        }

        .center {
            width: 59%;
            float: left;
            height: 500px;
        }

        .right {
            width: 20%;
            float: left;
            height: 500px;
        }

        .footer {
            clear: both;
            text-align: center;
            background: blue;
        }


    </style>


</head>
<body>
<div class="head">头</div>
<div class="navibar">导航</div>
<div class="left">左侧图片</div>
<div class="center">中间正文</div>
<div class="right">右侧图片</div>
<div class="footer">底部超链接</div>


</body>
</html>